Responsiveness and minimal important changes for the Neck Disability Index and the Neck Pain Disability Scale in Italian subjects with chronic neck pain

Abstract

The Italian NDI and NPDS were equally sensitive in detecting clinical changes in subjects with chronic NP undergoing rehabilitation. We recommend taking the MICs into account when assessing patient improvement or planning studies in this clinical context.

Responsiveness and minimal important change for the ProFitMap-neck questionnaire and the Neck Disability Index in women with neck–shoulder pain

“…The results suggest that both measures possess similar ability to detect change in self-rated perceived health with AUC exceeding 0.7 which is a cut-off value that has been used to delineate adequate responsiveness [40–43]. While this was the first examination of responsiveness for ProFitMap-neck, several previous studies exist on this measurement property for NDI [30, 34, 36, 40–42, 44–47]. Most of these show results in concordance with the present study, except for two studies that found lower AUC for NDI (0.57 [36] and 0.59 [44]).…”

“…However, pain frequency may still be important to measure in chronic pain clinical trials since temporal aspects of pain have shown to be a valid dimension discerned from pain intensity, therefore recommended as an outcome [31]. The MICs obtained for NDI are rather low compared with previous studies in chronic neck pain, showing a range of 5–19 % [30, 34, 36, 40–42, 44, 47, 52]. One explanation for this may be the low mean NDI baseline scores of 28 and 23 NDI% in sample I and II, respectively.…”

“…Association between NDI baseline scores and MIC was recently demonstrated, showing larger MIC for those above (i.e., with higher disability) compared to those below (i.e., with lower disability) median baseline score [42, 44, 52]. The same effect of baseline values on MIC in neck pain patients was also shown for pain intensity numerical rating scale [53], but not for Neck Pain Disability Scale [42]. In the comparison of MIC values of NDI and the ProFitMap-neck indices, the latter were slightly higher.…”

“…The comparison of the MIC of ProFitMap-neck with MIC of other neck-specific questionnaires beside NDI is hampered by the low number of studies and differing methodology to determine MIC. For comparable studies, Neck Pain and Disability Scale [41, 42] and Neck Bournemouth Questionnaire [54] had MIC of similar magnitude as ProFitMap-neck, whereas MIC reported for the Core Outcome Measure Index summary score was higher (20 and 27 %) [55, 56]. …”

“…The first concerns the validity of the external anchor. In line with many other studies [30, 34, 36, 40–42, 44–47, 53, 60], we used GRCS as the external anchor to discern improved versus no or little change. This method has been criticized, one reason being recall bias [32].…”